Screening for pulmonary arterial hypertension in systemic sclerosis

[The place of riociguat in the treatment of patients with pulmonary arterial hypertension associated with systemic connective tissue diseases]

Pulmonary hypertension (PH) can develop in different systemic autoimmune rheumatic diseases (SARD), such as systemic scleroderma (SSD), systemic lupus erythematosus, rheumatoid arthritis, and mixed connective tissue disease In most cases, patients with SARD develop WHO group I PH (pulmonary arterial hypertension associated with systemic connective tissue diseases, PAH-SCTD). General prevalence of this pathology reaches 15 cases per million adults. Most cases of PAH-SCTD are induced by SSD. Survival of PAH-SCTD patients is generally lower than survival of patients with other forms of LAH. Treatment of any SARD, including in LAH, implies a complex approach using glucocorticoids, disease-modifying anti-rheumatic drugs (cyclophosphamide, methotrexate, azathioprine, and others), and genetically engineered biologics. Specific targeted therapy is indicated for most patients with PAH-SCTD. The representative of a new class (soluble guanylate cyclase (sGC) stimulators), riociguat, has been approved for the treatment of PAH. This drug has a unique double mechanism of action: (i) sGC sensibilization to endogenous nitric oxide (NO) by stabilizing the NO-sGC bond; and (ii) direct, NO-independent sGC stimulation. For patients with PAH-SCTD, riociguat is the major alternative to phosphodiesterase-5 inhibitors both as monotherapy and combination therapy.

Associated factors of early-onset pulmonary hypertension and clinical difference between early- and late-onset pulmonary hypertension in Thai systemic sclerosis

OBJECTIVES

Pulmonary hypertension (PH) is a major cause of death in systemic sclerosis (SSc). Detection of early-onset PH and its associated factors would be helpful for improving patient care. Our aims were to determine the factors associated with early-onset PH and to define the differences between early- and late-onset PH among SSc patients.

METHODS

A cohort study was conducted of 409 adult SSc patients who had followed-up between January 2014 and December 2016. Early-PH is defined when the onset of PH is diagnosed within 5 years of the disease. Logistic regression analysis was applied to determine the factors associated with early-PH.

RESULTS

In 3409 person-years, we diagnosed 50 cases with PH confirmation by right heart catheterization, of whom 26 were early-PH (incidence 0.7 per 100 person-years; 95%CI:0.5-1.1). Among SSc with early-PH, 69.2% had the diffuse cutaneous SSc subset and the most common PH classification was PH due to interstitial lung disease (18 cases;69.2%). According to a logistic regression analysis, early-PH was associated with a WHO functional class (WHO-FC) II and higher, cardiomegaly according to chest radiography, and tricuspid regurgitation jet maximum velocity (TRVmax)>2.8 m/s with the respective OR of 20.12 (95%CI:1.59-255.35), 7.42 (95%CI:1.35-40.88), and 8.20 (95%CI:1.17-57.64). To contrast, early-PH had a negative association with gastrointestinal involvement (OR 0.08; 95%CI:0.01-0.56).

CONCLUSIONS

Early-PH is prevalent among SSc patients and the most common cause is interstitial lung disease. A poor WHO-FC, cardiomegaly, and a high TRVmax are associated with early-PH. Gastrointestinal involvement is a protective factor for early-PH in SSc.

Management of hyperuricemia in asymptomatic patients: A critical appraisal

While there is consensus on starting urate-lowering therapy (ULT) in cases of symptomatic hyperuricemia, the frequent condition of asymptomatic hyperuricemia (AH) remains a challenge due to differences in the findings of studies that have addressed the issue. Uric acid has anti-oxidant properties, but high levels predispose to gout and may play a role in metabolic syndrome. We systematically evaluated randomized controlled trials (RCTs) addressing ULT in patients with AH, to assess the current evidence. We found broad heterogeneity among the studies (13 RCTs), in terms of study design and population, making findings challenging to interpret and generalize; hard end-points were not assessed. Allopurinol is often prescribed for AH despite the fact that its use is not backed by conclusive evidence from prospective RCTs, nor is it recommended by the guidelines. Its potential benefits, in terms of absolute risk reduction, must be weighed against its potential for harm since it can trigger severe adverse hypersensitivity reactions, sometimes even fatal. RCTs with hard end-points are needed to assess the risk/benefit of lowering uric acid in subjects with AH, particularly as secondary prevention for cardiovascular risk and in patients with different degrees of renal disease. To date, particularly after the result from the CARES trial, preventive treatment of asymptomatic and non-severe hyperuricemia is not recommended.

Systemic sclerosis: Advances towards stratified medicine

Epidemiological studies reporting demographic, clinical and serological factors predictive of various outcomes in systemic sclerosis (SSc) range from the prediction of mortality to the development and progression of disease manifestations. However, predicting the disease trajectory in the individual patient is a challenging but important step towards a stratified approach to disease management. Recent technological advances provide the opportunity for new subgroupings of disease based on risk stratification, through the systematic analysis of high-dimensional clinical data combined with genes, their transcription products and their corresponding translated proteins. In addition, these variables offer a rich vein of research to identify non-invasive biomarkers for predicting organ involvement and to assess disease activity and response to therapy. Selection of patients with a clinical phenotype or molecular signature relevant to the therapy under study combined with recent efforts to standardise outcome measures, show promise for improving clinical trial design and the identification of effective targeted therapies.

Screening strategies for pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is rare and, if untreated, has a median survival of 2-3 years. Pulmonary arterial hypertension may be idiopathic (IPAH) but is frequently associated with other conditions. Despite increased awareness, therapeutic advances, and improved outcomes, the time from symptom onset to diagnosis remains unchanged. The commonest symptoms of PAH (breathlessness and fatigue) are non-specific and clinical signs are usually subtle, frequently preventing early diagnosis where therapies may be more effective. The failure to improve the time to diagnosis largely reflects an inability to identify patients at increased risk of PAH using current approaches. To date, strategies to improve the time to diagnosis have focused on screening patients with a high prevalence [systemic sclerosis (10%), patients with portal hypertension assessed for liver transplantation (2-6%), carriers of mutations of the gene encoding bone morphogenetic protein receptor type II, and first-degree relatives of patients with heritable PAH]. In systemic sclerosis, screening algorithms have demonstrated that patients can be identified earlier, however, current approaches are resource intensive. Until, recently, it has not been considered possible to screen populations for rare conditions such as IPAH (prevalence 5-15/million/year). However, there is interest in the use of artificial intelligence approaches in medicine and the application of diagnostic algorithms to large healthcare data sets, to identify patients at risk of rare conditions. In this article, we review current approaches and challenges in screening for PAH and explore novel population-based approaches to improve detection.